The present invention relates generally to devices for measuring gas leakage from sealed packages of various types, usually made from plastic film or molded plastic. More particularly, the invention relates to a device for providing a xe2x80x9ccalibrated leakxe2x80x9d to a package, which means that the invention, when applied to a package, allows a predetermined and precise amount of leakage from the package. The usefulness of the invention lies in the fact that it enables leak measurement equipment to receive a predetermined and known precise amount of leakage gas, thereby to permit calibration of the leakage measurement equipment to the known leakage. Once the leakage measurement equipment has been calibrated using the invention, subsequent packages can be measured to provide an accurate measure of the leakage from each subsequent package.
The invention relates particularly to the type of packaging described in copending U.S. application Ser. No. 09/845,914, entitled xe2x80x9cMulti-port Gas Leakage Measurement Fixture,xe2x80x9d filed Apr. 30, 2001, owned by the assignee of the present invention, and packages similarly constructed of plastics for the purpose of holding articles in a confined and relatively sterile, isolated environment.
It is a principle object of the present invention to provide a calibration tool for the measurement equipment which provides a measure of leakage from packages and the like.
It is another object of the present invention to provide a calibration tool which can be used by a variety of gas leakage equipment to provide a standard basis for calibrating all such equipment, thereby to provide measurement data which is valid for a number of different types of measurement equipment.
An advantage of the present invention is that it provides a quick and consistent calibration technique for many different measurement devices which might be in use at the same time, and thereby ensures that all such devices are providing data of the same or very similar accuracy.
Other and further objects and advantages of the invention will become apparent from the following specification and claims and with reference to the appended drawings.
A device for attachment to a package, including a deformable plug for insertion through a hole in the package, a bolt threadable into the plug, to cause deformity and sealing of the plug against the package wall as the bolt is tightened; the bolt has an axial passage which joins to a side passage through the head of the bolt, and an insert having a predetermined-size leak opening is press-fit into the axial passage. The insert has alternative forms: one form comprises a jewel such as sapphire having a precise hole drilled through it; a second form comprises a capillary tube having a precise internal diameter and a predetermined length.